Sharply Lower Gas Costs Promise to Give Boost to Consumer Spending

American workers have been waiting years for a big raise. That bump is finally coming—at the gas pump.

If prices were stay at their current levels under $3 a gallon, the American consumer could save an average of $380 during the coming year, up from $83 since prices first declined this past summer, according to research firm ClearView Energy Partners. A separate estimate from IHS Global Insight says the average family could save...